


Something New

by stuffedsterek



Category: Teen Wolf (TV)
Genre: Derek isn't against it, Fit!Derek, Gainer!Stiles, M/M, This a fic meant for adults, Weight Gain, don't fucking read this, eventual Fat!Stiles, feeder!derek, he might even be into it, if you don't want to read about kinky ass shit, this is a story of self realization on all fronts tbh, this is me letting all the children know not to read this fic
Language: English
Status: In-Progress
Published: 2018-11-24
Updated: 2018-12-11
Packaged: 2019-08-28 11:56:22
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 2,922
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16722888
Author URL: https://archiveofourown.org/users/stuffedsterek/pseuds/stuffedsterek
Summary: Their relationship was great, or at least Derek though so until he caught Stiles in a compromising position that sends their relationship on a whole new path.or the one where Stiles wants to gain and Derek is there for it.





	1. Chapter 1

**Author's Note:**

> This is kind of a reverse 5+1 times because I wanted to do a 5+1 times but like... i couldn't stand the idea of Stiles having to ~~try and~~ hide a kink of his for Derek's sake. So this is what I came up with! 1 time Derek sees Stiles deepest darkest kink, and 5 times he completely indulged in them (and learns along the way that it's his kink too).

The thing about dating someone just exiting the years of puberty, is that they’re kind of always in the mood for sex. Stiles wasn’t the most sexually active teenager, but now that he’s in college and dating Derek, he is seems to be trying to catch up on all the sex he didn’t have. 

Derek still knows that Stiles is masturbating even when he can get all the sex he wants. He can smell it on his boyfriend, and it’s starting to bother him… Not in like Derek won’t fuck Stiles speechless whenever he wants, but there seems to be something that Derek is incapable of doing for Stiles. 

He doesn’t quite know what Stiles would be hiding from him. The human has made it very clear about what kinks he’s willing to explore and what he is and isn’t comfortable doing in bed. So the secrecy of an unexplored kink makes Derek wonder what is so bad that Stiles isn’t willing to share it. 

Derek doesn’t have to wait to long before he finds out. 

It’s a normal Tuesday. And on a normal Tuesday such as this, Stiles is to be at the library until about 9, then he’ll make his way home to an empty dorm room and prepare himself for the next day. Today though, Derek is going to surprise Stiles because he knows his boyfriend has been a little extra tense, especially since it’s midterms right now. 

Derek waits for a neglectful freshman to leave the door open enough for him to sneak in. The elevator is creaking and probably hasn’t been inspected in like 15 years, but it gets him to the 6th floor where Stiles’ room is. There are smells and sounds that he wishes he never experienced because if he thought Stiles was a gross teenager, his peers must be another species of human to be living in the filth that they are. 

The door to Stiles’ dorm is at the end of the hall, which has made for some very… interesting walks back to his car. When Derek reaches the door, he pulls out his illegal copy of the key but is surprised to find that it isn’t locked, and noise is coming from inside. Derek looks at his watch to confirm the time. It’s only 8, Stiles should still be at the library… 

Then what the fuck is he doing in his dorm room? Immediately Derek focuses in his hearing to see if the small part of his brain convincing him that he wasn’t enough for Stiles and the horny college kid had to go somewhere else to satisfy his needs. Derek turns the handle, prepared to find Stiles wrapped around some other kids legs. He was afraid to see Stiles in the throes of passion with anyone that wasn’t him. With a deep breath, he pushes the door open and has to remember to draw back his red eyes just in case whoever he has in there isn’t supernatural. 

What he doesn’t expect… is Stiles in his bed… by himself with his laptop open and three empty boxes of pizza on the floor… one piece of pizza wrapped directly around his...

“Derek?!” Stiles yells, attempting to close the laptop where it sits on the bed in front of him, but Derek is too quick and he moves to stop the laptop from closing. Stiles throws his hands up, discarding the pizza topped with jizz to the floor. With a glare, Derek looks at the computer screen to face what the fuck Stiles was doing in here. 

The video on the computer is still running, and it's…. Not what Derek expected. Though, Derek doesn’t really know what he was expecting. 

On the screen is two men, obviously… but while one is of average size and stature, Derek might even be entertained to say that guy was his approximate size,  the other is morbidly obese. The smaller man looks like he’s humping into the fat guy’s belly button and…. 

Behind him Stiles comes. The video was about 45 seconds in. Damn, Stiles never came that fast with him. 

Derek shuts the laptop and looks around the room. He normally gives Stiles a heads up before he shows up, usually to avoid missing him or to make sure that he has time to hang out. But without warning, Derek gets to see how much of a fucking mess Stiles’ room is. Firstly, there are clothes everywhere. Like, an absurd amount of clothes. Stiles goes to pick one up only to find the pair of pants to be about 10 sizes to big for anyone he knows. 

Secondly, there is food  _ everywhere _ . No just food, but snacks, and sweets, and more snacks and more sweets, and empty boxes of Krispy Kreme Donuts, and Dunkin and KFC and Arby’s and so much fucking McDonald’s just strewn across the floor. Derek looks back to Stiles and really looks at him. He’s still shirtless, clothesless really. 

Sure Derek had noticed Stiles was a little… softer around the middle. He chucked it up to the freshman fifteen, now looking at Stiles, he looks like a completely different person from when they started dating, and Derek just, hadn’t noticed. 

Stiles’ pecs were soft, almost tit like, resting on his chest, his belly was beyond the pooch he was used to and was distended with what he presumes is food. There were angry red stretch marks underneath his belly button leading down to his dick. Silvery marks lined his thighs and Derek wonders how the hell he didn’t notice Stiles’ seemingly intentional weight gain. 

As Derek is doing his inspection, Stiles remains motionless on the bed, like maybe if he doesn’t move Derek won’t see him. It’s quiet between the two of them for a few moments, neither of them knowing what to do about this development. 

“Derek?” Stiles finally asks, and finally moving to grab the shorts that were discarded right next to the bed. “What - uhh what are you doing here?” His voice cracks and Derek can suddenly smell the humiliation and fear filling the room over the smell of pizza and sweets. 

“What am-? What are  _ you _ doing?” Derek asks, he’s not entirely sure if he is mad or sad or upset or… turned on?

“I can explain!” Stiles replies. Derek makes a face that says ‘go on’ and waits. “I uh-- well see it- there was this--” he kept starting, but he couldn’t get anywhere after that. 

“Is this what you’ve been hiding from me?” Derek asks, knowing that Stiles, for once, is at a loss for words. 

Stiles is standing now, looking at Derek from across the tiny room, “yes.” It’s filled with shame and embarrassment. Derek doesn’t like the look on Stiles. There has never been anything Stiles has been to ashamed of to share with him, at least until now. 

The air remains awkward between them. Derek turns to leave because this is… this is a lot to process. 

“Der?” Stiles asks, the rustle from behind him makes Derek thin that Stiles is standing up now. 

“I’ll call you tomorrow Stiles,” Derek throws over his shoulder. He doesn’t bother looking back to see what Stiles looks like. 

Sitting in his car, Derek stares out the windshield to realize that he has had no idea about this  _ desire _ Stiles has had. He’s confused about the whole thing, because for as long as Derek has known Stiles, he has never thought that this is something he would want. 

Derek thinks back to the video he saw Stiles watching. The contrast between the big and small guy, the sheer mass of the obese one. That’s what Stiles  _ wanted _ . Their last date comes to mind, Stiles got a large popcorn at the movies, but he also go three hotdogs, a slushie, and a couple boxes of candy. Derek paid and even  _ encouraged _ him to get them. 

His pants get tight, and he didn’t realize it until he unconsciously brings his hand down to stroke it out. The image of the two men on the laptop come back to mind, he unbuttons his jeans and thinks about them some more. Thinks about Stiles being that big, him needed someone to help him do anything because he’s so  _ big _ . The flushed red hugh of his cheeks as he would be pushed to the edge of absolute pleasure. Derek can imagine it, and before he knows it he’s coming all over his hand. 

“Fuck,” he breathes out as his orgasm fades. 


	2. Chapter 2

**Notes for the Chapter:**

> So i got a good response from the first part of this! Thanks to everyone who left a comment! I truly appreciate it! this is kind of a set up chapter i guess? more smut in the next one i promise!

Derek sits in his car and stares at the parking lot of the local mall. He knows he shouldn’t be here. His reaction was not the best, and he can’t even begin to wonder what the hell is going through Stiles’ head.

Slowly Derek manages to wrap his head around this whole thing. He remembers how Stiles has been gaining weight, but he always thought it was unintentional. Now though, it seems that he is doing this on purpose.

The more he thinks about it the more the idea of this being something they do together, the more it entices him. The video Stiles was playing goes through his mind too. Is that what Stiles would want? To be that big? The guy in the video was huge, bigger than Derek could have imagined a person could become.

Would Stiles want him to gain too? Though Derek is finding himself more and more okay with Stiles doing this, he can’t really imagine himself doing this too. But he _can_ see himself bringing Stiles food, and rubbing his belly, and just _helping._

Derek’s mind races with the questions, one popping up after another. A strange panic rises in his own mind, and he knows that instead of stewing in here by himself, he could actually talk to Stiles to get the answers to these questions.

Finally, Derek picks up his phone scrolls to Stiles’ name, which has a heart after it that Stiles put there himself, and hits call.

The phone rings a couple of times, and for a moment Derek doesn’t think that Stiles is going to answer. But then, the ringing stops and a sleepy, “Derek?” comes from the other line.

“Hey,” is all he can manage.

“Hey.” Between them the air falls dead. Derek doesn’t really know how to broach this subject, and doing it over the phone feels like a coward’s move. “Listen, Der I-” Stiles starts but instead Derek cuts him off and asks,

“Have you eaten?”

This seems to confuse Stiles, “what?”

“I’ll be by in a few, we can grab something to eat and talk.”

“O-okay?”

“Great, see you in a few,” Derek hangs up with no other conversation. The clock on the nightstand says it’s only 8:30, but that might be too late for a few restaurants. Quickly he googles what the hours are for the few chain buffets he knows. Golden Corral is open until 9:30, and then or course that’s when they stop letting people in, they could probably stay until ten before the staff really starts getting annoyed with them.

Derek slips on his jacket and heads out to his car.

The drive back to the dorms is weird, but when he gets there he sees Stiles waiting outside in a shirt and cargo shorts despite it being the middle of December. Derek doesn’t even have to honk or text Stiles that he arrived, because as soon as Stiles sees the car, he begins his approach. The lock on the door pops up after Derek hits the button on his side of the car and with all the grace Stiles can muster, he slips into the car.

“Hi.”

“Hi,” Stiles closes the door after him.

“Ready?” On the drive over, Derek had decided he was going to pretend the thing in the dorm room hadn’t happened. Well, it happened, but it was no big deal, because the more he thought about it, the more it was true.

“Uhhh… yeah?” Derek pulls away from the where he stopped the car and follows the streets to where he knows the Golden Corral is. They pull up and Stiles continues to look confused but gets out when Derek does. “You’re seriously taking me out to eat?” Stiles asks as they enter the establishment.

“Yes, you haven’t eaten yet,” Derek says. The girl at the counter looks annoyed that they’re walking in, even though there is still probably an hour before they close. “Two please,” Derek says and pulls out his wallet to pay.

“Bro, you know I’ve eaten,” Stiles says, but that doesn’t stop him from grabbing the trey the girl at the counter gives him.

“A little late night snack then,” Derek says and his stomach is full of butterflies. “Go find somewhere to sit, I’ll get you something.” Before Stiles can protest, Derek turns and heads for the rows and rows of food. He gets two plates, one for him and one for Stiles. On his he puts a steak and a dollop of potatoes and a bit of vegetables. On Stiles he puts two pizza slices, a burger, some curly fries, chicken strips, and he even grabs a seperate bowl just for mac and cheese that smells delicious. At the last minute he goes to the salad bar and pours a little bowl full of ranch dressing and adds it to the tray.

He looks back in the direction he came, and sees Stiles sitting at a table with his phone out. Derek takes a deep breath, trying to find the confidence to do this, for Stiles but also for him. Once the courage has been mustered, he starts to the table with the food on his tray.

“Here you go,” Derek sets Stiles’ plate down in front of him, and puts his own on his side of the table.

“Woah, this is a lot of food. I don’t think I can finish this,” Stiles says, picking up a fry and dropping it into his mouth.

“Yeah you can,” Derek takes a bite out his own food. Stiles skeptically picks up his fork and pokes at the mac and cheese. They sit in silence for a few minutes before Derek asks, “how are midterms going?” As much as Derek is trying to make this normal, and ignore the butterflies in his stomach, there is something that feels so wrong about this.

“What’s this about Derek?” Stiles sets his fork down on the table, his plate still looking untouched.

“What’s what about?” The butterflies in his stomach take over his body.

“ _This_ Derek. An hour ago you left me alone in my room, _disgusted_ by my- my-” he waves his arm around presumably motioning to his sexual escapade, “and now we’re sitting in a Golden Corral, and you put a plate of food in front of me like you didn’t just see me- doing what I was doing.” His voice was hushed, even though there wasn’t anyone really around.

“I’m uh-” Derek really has no idea how to deal with this. He puts his own fork down, “Stiles, seeing you-like that- it umm. Well it was kind of a shock,” Stiles leans back into his chair and crosses his arms over his chest, looking down with his cheeks flushed. Derek takes a deep breathe and continues,  “but- I think- I think I liked it?

“I know you’ve been hiding something from me. I was sure you were cheating on me or something. Considering the alternative, wou wanting to eat isn’t a big deal, and I think I want to help you.”

“I don’t just wanna eat Der. Being big, I like it and- I think I wanna get bigger. I don’t wanna drag you around if that’s not something you want.”

“I want you Stiles. And if you weren’t listening, I think- I think I want to help you. If you’ll let me.”

“Really? You’ll still love me when I’m fat?”

“I’ve waited my entire life for you Stiles, I’m not about to leave you because you want to gain weight.”

“Then we’re doing this?”

“Only if you want to,” Derek’s heart flutters. Without another word Stiles picks up his fork and starts attacking the pile of food in front of him. Derek takes that as a sign that he can pick up his own fork and start digging back into his food. The waitress comes by and refills their cups.

“Can you get me more of this mac?” Stiles ask when his plate is half empty.

“Of course babe,” Derek stands up and walks back to where the rows and rows of food still lay out under the heat lamps. He piles a soup bowl full of mac and cheese and gets another plate to pile with spaghetti and garlic bread. He’s halfway back to the table when he sees the row of dessert. Another plate gets piled high with two pieces of chocolate cake, pudding, jello, apple pie, and something called mudslide pie.

Derek sets the plates down on the table, his plate was taken in his absence.

“Whoa Der,” Stiles says looking at the new piles of food before him.

“You have to eat it all because they won’t let us take anything home,” Derek says taking his fork and cutting a small bit of cake off the dessert plate.

Stiles smiles his mouth full of food, “I love you.”

“Love you too,” Derek says and leans over the table to peck a kiss on Stiles’ cheek.

**Notes for the Chapter:**

> please leave a comment! I lvoe those guys.   
> umm i guess join me on [tumblr?](stuffedsterek.tumblr.com) I don't post toooo mcuh on there, i normaly just use it to creep on other tumblrs... but sometimes i post things!

**Author's Note:**

> so this is part one. I haven't really felt comfortable or confident in posting anything like this in a long time... so we'll see how this goes?


End file.
